Push-up

Push-up positions and range of motion are not a guess, or a suggestion: Arms (actually) straight at top, pointer fingers pointing forward, chest + hips + chin level at the bottom, hard, flat plank throughout.

Anything less or more is something else, and for a different reason.

Reminder: Scale accordingly to ensure both progress and safety; Leave the ego out of the equation- excellent, scaled push-ups are far better than crappy, broken “unscaled” ones.